1. Field of the Invention
The present invention relates to method and apparatus for image processing such as image reproduction.
2. Description of the Prior Art
At present there are widely used copying machines to reproduce original images. However, the kinds of image processing which the conventional copying apparatus can perform are very limited. For example, the functions of such conventional copying apparatus are limited only to reproduce the same image as the original, to reproduce magnified or minified images of the original or to change the image density of the original. To broaden the image processing function of the apparatus, in these years, there have been proposed various image processing apparatus in which the original image is read as electric signals by use of CCD and the image data electric signals are electrically processed for various purposes. In addition to the above mentioned conventional functions, these image processing apparatus can perform many other functions, for example, to make a reproduction of a particular extracted part of the original, to make a composite image from two or more different images or to selectively change the image density of a selected part of the original.
According to the prior art, these image processing works are realized by preparing many corresponding commands for individual functions of the apparatus and serial input of the commands by the operator as required. This processing system of the prior art has some drawbacks. Among them, the command input troubles the operator very much. The reason for this is that even for routine jobs it is required to carry out the input of commands in the same combination every time the routine task is to be performed.
As an improvement in image processing there has been also proposed to store plural different sets of image data in a memory. This method is used in particular when only a part of an original is extracted and the image data contained in the extracted part is reproduced as desired. According to the improved method (cf. Japanese Patent Application Laid Open Patent Application No. 140,630/1978), each of plural different data sets stored in the memory contains a set of address data including the extracted image data, the number of picture elements thereof measured in the principal scanning direction and the number of lines measured in the secondary scanning direction.
However, this method also has the drawback that in image processing, it is very difficult to find out the reproduction coordinates of the extracted image data.
Further, in case of the prior art image processing apparatus, a problem arises when image data are to be stored in a disc memory. In this case, the image data should be stored sequentially in such sequence of track/sector address as to minimize the access time to the disc. The method for use of such disc volume conventionally employed is to divide the whole disc area into a plural number of sections by the maximum file length (whole picture area) and to allocate them to particular files. Although this method has solved the problem of access time, it has another disadvantage, viz. that the efficiency of utility of the memory area is reduced thereby.
As the memory for storing image data or command data there may be used also a dynamic RAM. However, the use of such dynamic RAM has a disadvantage that periodical refreshing work is required to prevent the content of the memory from being lost. If the original document is read by CCD or the like so as to register the image data in such memory, the timing of data registration and the timing of data refreshing sometimes bring about a problem in keep the data in memory.
On the other hand, various display methods have already been processed and used to externally display the statues of the system. For example, whenever it is required, the processing by CPU is stopped for a while and the content of the memory is read out from a certain memory address in which the status of the system has been stored by operating some hardware. Also, direct display employing LED's is often used. For example, an LED (light emitting diode) is connected to the output of a sensor detection amplifier to use it for direct display by means of hardware. Also, when CPU detects any abnormal state such as error, LED may be lighted on by CPU program.
These displays also have some drawbacks. For example, it is impossible to read out the memory content in dynamic state during the operation of the system. Further, the number of display devices required increases with the number of kinds of information which the operator wishes to obtain.